Does Silver Iodide replace Collodion plus Iodide on Wet Collodion

Mustafa Umut Sarac

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Hello there,

I have just learned mixed collodion and iodide solution have been soaked in silver nitrate solution to make light sensitive silver iodide.

I found silver iodide is ready to be bought.

Does silver iodide or silver iodate replace collodion.

In Turkey collodion is a dangerous material to be sold or bought.

Mustafa Umut Sarac
Istanbul
 

AgX

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Collodion is just the binder, similar to gelatin. Though gelatin functions during processing in an aqueous environmment, collodion in an organic solvent envirionment, that still must be water-mixable.
Furthermore gelatin sets by cooling, collodion by evaporation. Gelatin interacts with the photochemical process, collodion is inert.
 

koraks

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Like AgX says, the collodion is the binder and thus, the light sensitive compound does not replace the binder. In addition, in a typical collodion mix, you have both silver bromide and silver iodide, although only silver iodide will also produce an image. If you buy silver iodide as is, the main problem is that you don't know (but I think you can safely assume) that it is already exposed either optically or chemically and upon development, it will therefore develop completely and not just the image you're trying to record. If collodion is problematic to purchase, you may consider making gelatin-based dry plates instead. Btw, I'd be surprised if collodion cannot be bought in Turkey, but I'm not sure about local regulations. If any particular ingredient is difficult to obtain, it will most likely be cadmium salts (which you can do without) and pure ether (which can also be left out if you use a formula that requires no additional ether such as Poe Boy).

Hence, if you want to start out with wet plate, I think it pays to look a bit further into potential sources for materials. I can hardly imagine that they cannot be obtained one way or the other in Turkey.
 
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Mustafa Umut Sarac

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I have overdosed with supply expenses , import and shipping expenses , low value turkish lira. I am cutting here. I decided to make my alt photo by bitumen. Its nasty but not outdoors. I asked petrograph photographic process question.
 

koraks

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Yes, I've seen it. But it's not really a substitute for wet plate, is it? See my previous remark on lack of speed and image quality.
 
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Mustafa Umut Sarac

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Petrograph is expressionist and ultimately easy to do. I went to drawing course for 2 years and I would die to draw like it. I am thinking to do it on glass .
 

J 3

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It might be noted that wet plate collodian can be done in pure ethyl alcohol eliminating the need for ether which can be hard to come by depending on your local. Furthermore featured ethyl will work (according to a John Coffer book I have. I've not tried it). Water has to be kept away from it because if it drops much below the 95% proof the cellulose nitrate stops dissolving. Also hypo works fine for a fixer. That doesnt get one out of silver nitrate. The silver salts have to be made in site because even a tiny amount of reduced silver mixed in will develop to a fogged plate.
 

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P.S. I meant denatured not featured. Spell checking was a bit aggressive.
 

koraks

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Denatured alcohol does work. I always use it, and I also only use collodion formulas without additional ether. They work fine, but it seems they age MUCH faster than more traditional formulas and have a fairly short lifetime of about one month before they get too slow to be useful.
 

AgX

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What is behind denatured alcohol depends on market. Over here it is Ethanol added by a repellant compound. Thus you would add another chemical (3 in the EU).
 

J 3

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It's usually another alcohol (methyl or iso-prop) down here. It doesn't affect the base chemistry enough to keep things from working provided the water content can be kept lower. I don't know how they denature alcohol in other countries. Getting 190 proof non-denatured alcohol might be easier or harder depending on where you are at.
 

J 3

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koraks said:
....They work fine, but it seems they age MUCH faster than more traditional formulas and have a fairly short lifetime of about one month before they get too slow to be useful.
Click to expand...
Thanks for this. I've got a todo to try these mixes. It's really helpful to know what to expect.
 
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